Tumor necrosis factor-α (TNF-α) and interleukin-1 (IL-1) are proinflammatory cytokines that mediate inflammatory responses associated with infectious agents and other cellular stresses. Overproduction of cytokines such as IL-1 and TNF-α is believed to underlie the progression of many inflammatory diseases including rheumatoid arthritis (RA), Crohn's disease, inflammatory bowel disease, multiple sclerosis, endotoxin shock, osteoporosis, Alzheimer's disease, congestive heart failure, and psoriasis among others (Dinarello, C. A. et al., Rev. Infect. Diseases 1984, 6:51; Salituro et al., Curr. Med. Chem. 1999, 6:807-823; Henry et al., Drugs Fut. 1999, 24:1345-1354). An accepted therapeutic approach for potential drug intervention in these conditions is the reduction of proinflammatory cytokines such as TNF-α (also referred to as TNFa) and interleukin-1β (IL-1b).
Recent data from clinical trials support the use of protein antagonists of cytokines, for example soluble TNFa receptor fusion protein (etanercept) (Moreland et al., Ann. Intern. Med. 1999, 130:478-486) or the monoclonal TNFa antibody (Enbrel) for the treatment of rheumatoid arthritis, Crohn's disease, juvenile chronic arthritis and psoriatic arthritis (Rankin et al., Br. J. Rheumatol. 1995, 34:334-342; Galadari et al. Int J Dermatol. 2003, 42:231-7; Reimold, Am J Med Sci. 2003 325(2):75-92). Thus, small molecules that inhibit or antagonize the effects of cytokines such as, for example, TNFa and or IL-1b are expected to be beneficial for the treatment rheumatoid arthritis, Crohn's disease, juvenile chronic arthritis and psoriatic arthritis.
Il-1 is detected in synovial fluid and in cartilage matrix joints of patients with osteoarthritis. IL-1 antagonists have been shown to diminish the degradation of cartilage matrix components in a variety of experimental models of arthritis (Chevalier, Biomed Pharmacother. 1997, 51:58).
Il-1 receptor antagonists have been evaluated in humans (Bresnihan et al., Arthritis Rheum. 1998, 41:2196-2204). Efficacy has been demonstrated for the treatment of rheumatoid arthritis (Antril, Amgen). Il-1 receptor antagonist also demonstrated reduced mortality in a group of patients with septic shock syndrome (Dinarello, Nutrition 1995, 11:492).
Cytokines such as IL-1 and TNFa are potent stimulators of nitric oxide (NO) production. NO is a mediator of cardiovascular homeostasis, neurotransmission, immune function and a modulator of bone remodeling with effects on osteoblasts and osteoclasts (van't Hof, Immunology 2001, 103(3):255-61 Evans, et al., J. Bone Miner. Res. 1996, 11:300).
IL-1 has also been linked to beta-cell destruction which is one of the hallmarks of insulin dependent diabetes mellitus. Although other factors can also mediate beta-cell damage, Il-1 is linked to this process through its effect on cyclooxygenase II (COX-2) and inducible NO synthase (McDaniel et al., Proc Soc Exp Biol Med. 1996, 211:24).
IL-1 has also been shown to induce uveitis in rats which could be inhibited with IL-1 blockers. (Xuan et al., J. Ocular Pharmacol. and Ther. 1998, 14: 31). Cytokines including IL-1, TNFa and GM-CSF have been shown to stimulate proliferation of acute myelogenous leukemia blasts (Bruserud, Leukemia Res. 1996, 20: 65). IL-1 was shown to be essential for the development of both irritant and allergic contact dermatitis. Epicutaneous sensitization can be prevented by the administration of an anti-IL-1 monoclonal antibody before epicutaneous application of an allergen (Muller, et al., Am J Contact Dernat. 1996, 7: 177). Data obtained from IL-1 knock out mice indicates the critical involvement in fever for this cytokine (Kluger et al., Clin Exp Pharmacol Physiol. 1998, 25: 141). A variety of cytokines including TNFa, IL-1, IL-6 and IL-8 initiate the acute-phase reaction which is stereotyped in fever, malaise, myalgia, headaches, cellular hypermetabolism and multiple endocrine and enzyme responses (Beisel, Am J Clin Nutr. 1995, 62: 813). The production of these inflammatory cytokines rapidly follows trauma or pathogenic organism invasion.
Rhinovirus triggers the production of various proinflammatory cytokines, predominantly IL-8, which results in symptomatic illnesses such as acute rhinitis (Winther et al., Am J Rhinol. 1998, 12: 17).
Cytokine inhibitors are also expected to block inducible COX-2, an enzyme involved in inflammation (M. K. O'Banion et al., Proc. Natl. Acad. Sci. USA 1992, 89:4888). Cytokine inhibitors such as, for example, IL-1 receptor antagonist (IL-1ra) would be expected to show efficacy against disorders where COX-2 inhibitors (such as the NSAIDs) would be used. These disorders include but are not limited to inflammatory diseases, chronic pain and cardiovascular disease.
Several cytokines are known to be elevated in inflammatory bowel disease (IBD) conditions. An imbalance of IL-1 and IL-1ra has been described in patients with IBD. Insufficient production of IL-1ra could at least partially contribute to the pathogenesis of IBD (Cominelli, et al. Aliment Pharmacol. Ther. 1996, 10:49).
Beta-amyloid protein deposits, neurofibrillary tangles and cholinergic dysfunction throughout the hippocampal region have been observed in Alzheimer's disease patients. Sustained levels of cytokines, such as, for example IL-1 and/or TNFa could be at least partially responsible for the damage in the brains of Alzheimer's disease patients (Grammas, Neurobiol. Aging 2001, 22(6):837-42; Rempel, J. Neurochem. 2001, 78(3):640-645).
Cytokines such as TNFa and Il-1 have been also implicated in the pathogenesis of human immunodeficiency virus (HIV) infection and acute inflammatory events (Kreuzer, Clin. Exp. Immunol. 1997, 109(1):54-58; Baqui, Immunopharmacol Immunotoxicol 2000, 22(3):401-421). The concentrations of cytokines and receptors are elevated in bone marrow supernatant of HIV-infected patients with hematologic abnormalities, and these concentrations were shown to correlate with clinical parameters in these patients (Dallalio, J. Investig. Med. 1999, 47(9):477-483).
Proinflammatory cytokines such as TNFa and IL-1b and interleukin-6 (IL-6) are important mediators of septic shock, cardiopulmonary dysfunction, acute respiratory distress syndrome (ARDS) and multiple organ failure. Patients admitted with presumed sepsis have elevated cytokine levels compared with patients with sepsis who are discharged and with those patients with presumed noninfectious systemic inflammatory response syndrome (SIRS) suggesting an association between cytokines and subsequent septic complications in these patients (Terregino, Ann. Emerg. Med. 2000, 35(1):26-34).
Cytokine imbalance is also implicated in cachmeriana and muscle degradation associated with HIV infection. The serum concentrations of inflammatory (IL-1b, TNFa, IL-6) and regulatory cytokines (Interleukin twelve) have been studied in ten AIDS cachectic patients and compared to a control group. A cytokine imbalance and a significant increase in proinflammatory cytokines (IL-1, IL-6, TNFa) was observed in the patient group (Baronzio, In Vivo 1999, 13(6):499-502).
Obesity is associated with an increase incidence of infection, diabetes and cardiovascular disease. Abnormalities in TNFa expression have been noted for each of the above conditions (Loffreda, et al., FASEB J. 1998, 12: 57). It has been proposed that elevated levels of TNFa are involved in other eating related disorders such as anorexia and bulimia nervosa. Pathophysiological parallels are drawn between anorexia nervosa and cancer cachexia (Holden, et al., Med Hypotheses 1996, 47: 423). An inhibitor of TNFa production, HU-211, was shown to improve the outcome of closed brain injury in an experimental model (Shohami, et al., J Neuroimmunol. 1997, 72: 169).
There is mounting evidence that inflammation plays a role in the development of coronary heart disease (CHD) and coronary artery disease (CAD). Elevated concentrations of acute phase reactants, such as C-reactive protein (CRP), are found in patients with acute coronary syndromes, and predict future risk in apparently healthy subjects. Cytokines such as TNFa, Il-1 and Il-6 have been suggested to promote atherosclerosis and heart disease. Coronary disease patients are characterized by increased serum concentrations of TNFa. It seems likely that immune activation (TNFa, soluble TNF receptors 1 and 2 (sTNFR 1, sTNFR 2), and interleukin-10 (IL-10)) in coronary patients is related to serum lipid levels (Mizia-Stec, Acta Cardiol. 2003, 58(1):9-15).
A large percentage of acute coronary syndrome is the consequence of unstable plaque rupturing, followed by thrombus formation. A characteristic of these unstable plaque is an increase in inflammatory cells (macrophages and T lymphocytes). The serum concentration of CRP (C-reactive protein) might reflect the amount of inflammation within atherosclerotic plaque and thus might provide a measurement of the instability of the plaque. CRP is believed therefore to have a predictive value for the occurrence of plaque rupture. Furthermore, there are indications that CRP itself is active in the inflammatory process. Studies have shown that so-called high-sensitivity CRP (hsCRP) measurements could be used as a tool for determining the risk for acute coronary syndromes. Antiinflammatory agents, capable of reducing the levels of hsCRP might contribute to reducing the risk of plaque rupture (Abjil, Ned Tijdschr Geneeskd 2003, 147(1):15-20; Branger, J. Immunol. 2002, 168(8):4070-7).
Elevated TNFa levels have also been found to be associated with congestive heart failure, and levels of cytokines have been correlated with the severity of the disease. Serum levels of TNFa are elevated in patients with heart failure, and both cardiac and infiltrating cells of the myocardium can produce this proinflammatory cytokine. Studies in both animal models and clinical investigations suggest that anti-TNFa therapies may limit the pathophysiologic consequences of congestive heart failure (McTiernan, Curr. Cardiol. Rep. 2000, 2(3):189-97). Furthermore, treatment with etanercept (a soluble TNF receptor) led to a significant dose-dependent improvement in left ventricular ejection fraction and remodeling, and there was a trend toward improvement in patient functional status, as determined by clinical composite score (Bozkurt, Circulation 2001 Feb. 27;103(8):1044-7).
TNFa levels are elevated in airways of patients with chronic obstructive pulmonary disease and it may contribute to the pathogenesis of this disease (M. A. Higham et al., Eur. Respiratory J. 2000, 15: 281). Circulating TNFa may also contribute to weight loss associated with this disease (N. Takabatake et al., Amer. J. Resp. & Crit. Care Med. 2000, 161 (4 Pt 1): 1179). Elevated TNFa levels have also been found to be associated with congestive heart failure and the level has been correlated with severity of the disease (A. M. Feldman et al., J. Amer. College of Cardiology 2000, 35: 537). In addition, TNFa has been implicated in reperfusion injury in lung (Borjesson et al., Amer. J. Physiol. 2000, 278: L3-12), kidney (Lemay et al., Transplantation 2000, 69: 959), and the nervous system (Mitsui et al., Brain Res. 1999, 844: 192). Proinflammatory cytokines are also known to play roles in ischemia-reperfusion injury of the heart, kidney, small bowel, skin, and liver. For example, TNFa and IL-1beta were shown to help regulate the development of lung ischemia-reperfusion injury. They appear to promote injury by altering expression of proinflammatory and anti-inflammatory cytokines. Neutrophil recruitment and lung neutrophil accumulation was markedly reduced among animals receiving anti-TNFa and anti-IL-1beta and combination blockade afforded even greater protection (Krishnadasan, J. Thorac. Cardiovasc. Surg. 2003, 125(2):261-72). In brain injury, pretreatment with intravenous anti-TNFa antibody reduced cortical and subcortical injury, enhanced cerebral blood flow during reperfusion, and improved the neurologic outcome. This supports the contention that TNFa is a deleterious cytokine in stroke, whereas circulating antibody against TNF-alpha may protect brain from reperfusion injury (Lavine, J. Cereb. Blood Flow Metab. 1998, 18(1):52-8; Mitsui, Brain Res. 1999, 844(1-2):192-5). TNFa is also believed to be released from the kidney in response to, and has been implicated in the pathogenesis of, renal ischemia-reperfusion injury (Donnahoo, J. Urol. 1999, 162(1):196-203).
Skeletal mass is maintained by a balance between cells which resorb bone (osteoclasts) and cells which form bone (osteoblasts). Recent observations have identified members of the TNF family of ligands and receptors as critical regulators of osteoclastogenesis (Horowitz, Cytokine Growth Factor Rev 2001, 12(1):9-18) and it was suggested that cytokines such as TNFa and IL-1 alpha may play an important role in pathological bone resorption. Data support the concept that TNFa is involved critically in osteoclastogenesis and bone resorption during periprosthetic osteolysis and suggest that TNFa inhibitors may be useful as therapeutic agents for the treatment of diseases involving bone resorption (Childs, J. Bone Miner. Res. 2001, 16(2):338-47; Abu-Amer, J. Biol. Chem. 2000, 275(35):27307-10).
Periodontal disease is a significant cause of tooth loss among adults and is characterized by the alteration and permanent destruction of the deeper periodontal tissues. Studies showed that IL-1 and TNF antagonists significantly reduced the loss of connective tissue attachment and the loss of alveolar bone height. This suggests that the loss of connective tissue attachment and progression of periodontal disease can be retarded by antagonists to cytokines such as IL-1 (Delima, J. Clin. Periodontol. 2001, 28(3):233-40).
TNFa plays a role in many aspects of glomerulonephritis progression. Studies showed that neutralization of endogenous TNFa is effective in preventing acute glomerular inflammation and crescent formation (Karkar, Nephrol. Dial. Transplant 2001, 16(3):518-24).
Ulcerative colitis (UC) and Crohn's disease (CD) comprise a series of inflammatory bowel diseases (IBD) resulting from chronic upregulation of the mucosal immune system and elevated levels of cytokines such as, for example, TNFa, IL1-b and IL-6. Strategies aimed at reducing cytokine levels, such as TNFa in patients with inflammatory bowel disease include the mouse/human chimeric monoclonal antibody infliximab, the humanized monoclonal antibody CDP571, the human soluble TNF p55 receptor onercept, the human monoclonal antibody D2E7 (adalimumab), the anti-TNF human antibody Fab′ fragment-polyethelene glycol (PEG) conjugate CDP870, and the small molecules thalidomide and CNI-1493 MAP-kinase inhibitor (Escher et al., Inflamm. Bowel. Dis. 2003 January; 9(1):34-58; Sandbor et al., Best Pract. Res. Clin. Gastroenterol. 2003, 17(1):105-17).
Abnormalities in the immune response are believed to play a role in the pathogenesis of hypertension. Studies showed that hypertensive patients had an increased IL-1 and IL-6 production capacity when whole blood was stimulated ex vivo with lipopolysaccharide (Peeters, Eur. J. Clin. Invest. 2001, (1):31-6). Inducible nitric oxide synthase (iNOS) present in vascular smooth muscle cells (VSMC) were suggested to play a role in the generation of nitric oxide (NO) in the vascular wall, regulating blood vessel tone in normotension and hypertension. IL-1 beta was shown to control iNOS gene expression at the transcriptional level (Singh, Am. J. Hypertens. 1996, (9):867-77) suggesting that agents inhibiting cytokines such as IL-1 inhibitors could be useful for the treatment of hypertension.
Diseases that are effected by IL-8 include myocardial ischemia and reperfusion, inflammatory bowel disease and many others.
The proinflammatory cytokine IL-6 has been implicated with the acute phase response. IL-6 is a growth factor in a number in oncological diseases including multiple myeloma and related plasma cell dyscrasias (Treon, et al., Current Opinion in Hematology 1998, 5: 42). It has also been shown to be an important mediator of inflammation within the central nervous system. Elevated levels of IL-6 are found in several neurological disorders including AIDS dementia complex, Alzheimer's disease, multiple sclerosis, systemic lupus erythematosus, CNS trauma and viral and bacterial meningitis (Gruol, et al., Molecular Neurobiology 1997, 15: 307). IL-6 also plays a significant role in osteoporosis. In murine models it has been shown to effect bone resorption and to induce osteoclast activity (Ershler et al., Development and Comparative Immunol. 1997, 21: 487). Marked cytokine differences, such as IL-6 levels, exist in vivo between osteoclasts of normal bone and bone from patients with Paget's disease (Mills, et al., Calcif Tissue Int. 1997, 61: 16). A number of cytokines have been shown to be involved in cancer cachexia. The severity of key parameters of cachexia can be reduced by treatment with anti IL-6 antibodies or with IL-6 receptor antagonists (Strassmann, et al., Cytokins Mol Ther. 1995, 1: 107). Several infectious diseases, such as influenza, indicate IL-6 and IFN alpha as key factors in both symptom formation and in host defense (Hayden, et al., J Clin Invest. 1998, 101: 643). Overexpression of IL-6 has been implicated in the pathology of a number of diseases including multiple myeloma, rheumatoid arthritis, Castleman's disease, psoriasis and post-menopausal osteoporosis (Simpson, et al., Protein Sci. 1997, 6: 929). Compounds that interfered with the production of cytokines including IL-6, and TNFa were effective in blocking a passive cutaneous anaphylaxis in mice (Scholz et al., J. Med. Chem. 1998, 41: 1050).
GM-CSF is another proinflammatory cytokine with relevance to a number of therapeutic diseases. It influences not only proliferation and differentiation of stem cells but also regulates several other cells involved in acute and chronic inflammation. Treatment with GM-CSF has been attempted in a number of disease states including burn-wound healing, skin-graft resolution as well as cytostatic and radiotherapy induced mucositis (Masucci, Medical Oncology 1996, 13: 149). GM-CSF also appears to play a role in the replication of human immunodeficiency virus (HIV) in cells of macrophage lineage with relevance to AIDS therapy (Crowe et al., Journal of Leukocyte Biology 1997, 62: 41). Bronchial asthma is characterized by an inflammatory process in lungs. Involved cytokines include GM-CSF amongst others (Lee, J R Coll Physicians Lond 1998, 32: 56).
Interferon-gamma (IFN-gamma) has been implicated in a number of diseases. It has been associated with increased collagen deposition that is a central histopathological feature of graft-versus-host disease (Parkman, Curr Opin Hematol. 1998, 5: 22). Following kidney transplantation, a patient was diagnosed with acute myelogenous leukemia. Retrospective analysis of peripheral blood cytokines revealed elevated levels of GM-CSF and IFN-gamma. These elevated levels coincided with a rise in peripheral blood white cell count (Burke, et al., Leuk Lymphoma. 1995, 19: 173). The development of insulin-dependent diabetes (Type 1) can be correlated with the accumulation in pancreatic islet cells of T-cells producing IFN-gamma (Ablumunits, et al., J Autoimmun. 1998, 11: 73). IFN-gamma along with TNFa, IL-2 and IL-6 lead to the activation of most peripheral T-cells prior to the development of lesions in the central nervous system for diseases such as multiple sclerosis (MS) and AIDS dementia complex (Martino et al., Ann Neurol. 1998, 43: 340). Atherosclerotic lesions result in arterial disease that can lead to cardiac and cerebral infarction. Many activated immune cells are present in these lesions, mainly T-cells and macrophages. These cells produce large amounts of proinflammatory cytokines such as TNFa, IL-1 and IFN-gamma. These cytokines are thought to be involved in promoting apoptosis or programmed cell death of the surrounding vascular smooth muscle cells resulting in the atherosclerotic lesions (Geng, Heart Vessels 1997, Suppl 12: 76). Allergic subjects produce mRNA specific for IFN-gamma following challenge with Vespula venom (Bonay, et al., Clin Exp Immunol. 1997, 109: 342). The expression of a number of cytokines, including IFN-gamma has been shown to increase following a delayed type hypersensitivity reaction thus indicating a role for IFN-gamma in atopic dermatitis (Szepietowski, et al., Br J Dermatol. 1997, 137: 195). Histopathologic and immunohistologic studies were performed in cases of fatal cerebral malaria. Evidence for elevated IFN-gamma amongst other cytokines was observed indicating a role in this disease (Udomsangpetch et al., Am J Trop Med Hyg. 1997, 57: 501). The importance of free radical species in the pathogenesis of various infectious diseases has been established. The nitric oxide synthesis pathway is activated in response to infection with certain viruses via the induction of proinflammatory cytokines such as IFN-gamma. (Akaike, et al., Proc Soc Exp Biol Med. 1998, 217: 64). Patients, chronically infected with hepatitis B virus (HBV) can develop cirrhosis and hepatocellular carcinoma. Viral gene expression and replication in HBV transgenic mice can be suppressed by a post-transcriptional mechanism mediated by IFN-gamma, TNFa and IL-2 (Chisari, et al., Springer Semin Immunopathol. 1995, 17: 261). IFN-gamma can selectively inhibit cytokine induced bone resorption. It appears to do this via the intermediacy of nitric oxide (NO) which is an important regulatory molecule in bone remodeling. NO may be involved as a mediator of bone disease for such diseases as: the rheumatoid arthritis, tumor associated osteolysis and postmenopausal osteoporosis (Evans, et al., J Bone Miner Res. 1996, 11: 300). Studies with gene deficient mice have demonstrated that the IL-12 dependent production of IFN-gamma is critical in the control of early parasitic growth. Although this process is independent of nitric oxide the control of chronic infection does appear to be NO dependent (Alexander et al., Philos Trans R Soc Lond B Biol Sci 1997, 352: 1355). NO is an important vasodilator and convincing evidence exists for its role in cardiovascular shock (Kilboum, et al., Dis Mon. 1997, 43: 277). IFN-gamma is required for progression of chronic intestinal inflammation in such diseases as Crohn's disease and inflammatory bowel disease (IBD) presumably through the intermediacy of CD4+lymphocytes probably of the THI phenotype (Sartor, Aliment Pharmacol Ther. 1996, 10 Suppl 2: 43). An elevated level of serum IgE is associated with various atopic diseases such as bronchial asthma and atopic dermatitis. The level of IFN-gamma was negatively correlated with serum IgE suggesting a role for IFN-gamma in atopic patients (Teramoto et al., Clin Exp Allergy 1998, 28: 74).
Recently it was shown that cytokine pathways play a role in the derivation and maintenance of embryonic stem cells (ES cells) (Proc Natl Acad Sci USA. 2004, 101: 6027), suggesting the potential application of cytokine inhibitors in conjunction with stem cell therapy.
WO 01/01986 discloses particular compounds alleged to having the ability to inhibit TNFa. The specific inhibitors disclosed are structurally distinct from the novel compounds disclosed in the present application disclosed herein below. Certain compounds disclosed in WO 01/01986 are indicated to be effective in treating the following diseases: dementia associated with HIV infection, glaucoma, optic-neuropathy, optic neuritis, retinal ischemia, laser induced optic damage, surgery or trauma-induced proliferative vitreoretinopathy, cerebral ischemia, hypoxia-ischemia, hypoglycemia, domoic acid poisoning, anoxia, carbon monoxide or manganese or cyanide poisoning, Huntington's disease, Alzheimer's disease, Parkinson's disease, meningitis, multiple sclerosis and other demyelinating diseases, amyotrophic lateral sclerosis, head and spinal cord trauma, seizures, convulsions, olivopontocerebellar atrophy, neuropathic pain syndromes, diabetic neuropathy, HIV-related neuropathy, MERRF and MELAS syndromes, Leber's disease, Wemicke's encephalopathy, Rett syndrome, homocysteinuria, hyperprolinemia, hyperhomocysteinemia, nonketotic hyperglycinemia, hydroxybutyric aminoaciduria, sulfite oxidase deficiency, combined systems disease, lead encephalopathy, Tourett's syndrome, hepatic encephalopathy, drug addiction, drug tolerance, drug dependency, depression, anxiety and schizophrenia. WO 02/32862 discloses that inhibitors of pro-inflammatory cytokines including TNFa are allegedly useful for treating acute and chronic inflammation in the lung caused by inhalation of smoke such as cigarette smoke. TNFa antagonists are apparently also useful for the treatment of endometriosis, see EP 1022027 A1. Infliximab, in clinical trials for RA, has also been indicated to be useful for treating various inflammatory diseases including Behcet's disease, uveitis and ankylosing spondylitis. Pancreatitis may also be regulated by inflammatory mediator production (J Surg Res 2000, 90(2):95-101; Shock 1998, 10(3):160-75.)
It is known in the art that anti-inflammatory compounds such as cytokine inhibitors can be used in combination with other active ingredients in the treatment of diseases and pathological conditions. For example, cytokine inhibitors have been combined with anti-cholinergics for the purpose of treating respiratory tract diseases (see WO03/084539 and corresponding US application 2003/0225089, and WO2004/004725 and corresponding US application 2004/0044020). Combination therapy with cytokine inhibitors and a variety of other active ingredients is disclosed in US patent application 2004/0110755.
The need for new therapies is especially important in the case of arthritic diseases. The primary disabling effect of osteoarthritis, rheumatoid arthritis and septic arthritis is the progressive loss of articular cartilage and thereby normal joint function.
TNFa plays an important role in many cell types in mediating responses to an external stimulus, such as, for example, an infection, trauma or a mitogen.
Thus, a need exists for therapeutics useful in the treatment of cytokine mediated diseases. While some protein therapeutics have been developed, they suffer from bioavailability and stability problems. In particular, there is a need for low molecular weight compounds that inhibit TNFa and/or IL-1b production.